1. Technical Field
The present invention relates to a test apparatus and a test method.
2. Related Art
A test apparatus for testing a semiconductor device inputs a prescribed test pattern into the semiconductor device and judges the acceptability of the semiconductor device by acquiring a signal sent by the semiconductor device in response to the input test pattern. If it is necessary to measure the waveform or the like of the signal output by the semiconductor device during testing, an external instrument such as an oscilloscope is connected to the test apparatus to acquire the signal.
The test apparatus includes a test module that tests the semiconductor device and a trigger generating module that connects the external instrument to the semiconductor device, and can therefore cause the external instrument to operate while simultaneously outputting the test pattern to the semiconductor device. In order to measure the waveform in synchronization with the test timing of the semiconductor device, it is necessary to synchronize the timing at which the external instrument acquires the signal with the test timing of the semiconductor device. Therefore, the test module and the trigger generating module include the same synchronization circuit to operate according to a common reference signal. Such a method for achieving synchronization between modules is disclosed in, for example, Japanese Patent Application Publication No. 2005-91037.
If the setting of only one of the modules is changed such that each module has a different synchronization circuit, however, synchronization cannot be achieved between the modules. As a result, when changing a setting of one of the synchronization circuits, it is necessary to apply the same setting change to the synchronization circuits of both the test module and the trigger generating module.